1. Field of the Invention
The invention relates to a power supply system and a control method thereof. More particularly, the invention relates to a countermeasure for an obstruction near a system that contactlessly supplies power.
2. Description of the Related Art
A non-contact power supply system that uses electromagnetic induction is known. For example, Japanese Patent Application Publication No. 2001-258182 (JP-A-2001-258182) describes one such a non-contact power transmitting apparatus. FIG. 13 shows the structure of this related art. This power transmitting apparatus contactlessly supplies power between a main body 1 that has a first coil 6 which receives power supplied from a commercial power supply, and a terminal 2 that has a second coil 7 which is coupled by electromagnetic induction to the first coil 6. A temperature increase preventing device which automatically stops the supply of power to the terminal 2 when a temperature equal to or greater than a predetermined temperature is detected is provided in the main body 1.
In this power transmitting apparatus, the supply of power is stopped in response to an increase in temperature. However, if an object or a person approaches the power transmitting apparatus while power is contactlessly being supplied, this is unable to be detected. That is, when using a non-contact power supply system with a facility such as a power supply station as the power transmitting side and a movable body such as a vehicle as the power receiving side, and power is contactlessly supplied to the movable body, it is possible that an occupant of a vehicle or the like may come near the power supply system, in which case it is desirable to quickly stop supplying power.